Morning coffee in Placentia and the talk centers around what happened Tuesday night. Thousands of people in Orange County felt something between 9 and 9:30 p.m.
"At about 9 o'clock, I'd say, there was a mild shaking," said Fullerton resident Daniel Ungerleider. "I felt my windows rattling a lot, and it was only for about 10 seconds."
A number of law enforcement agencies logged calls at the same time Tuesday night.
"Most of the people, it was that somebody was either jiggling the door knob, or the door itself, or there was some movement on the window making them believe that there was a prowler," said Sgt. Rick Martinez, Anaheim Police Dept.
"I was just sitting there with my roommate watching TV, and all of a sudden it was just like, I heard my windows shaking and we were kind of moving a little bit and I looked at her and I was like, 'Was that an earthquake?'," said Fullerton resident Olivia Vazques. "She's like, 'I don't know.'"
According to U.S. Geological Survey officials, they did not record any earthquakes Tuesday night that would be felt across the county. The National Weather Service says there were no reports of strong wind or unusual weather.
"I've seen a lot of action in the sky. You know, a lot of rocket, kind of missile-looking kind of things going on," said Placentia resident Laura Meloni.
After reviewing data, USGS officials say what they believe rattled windows did in fact come from the sky, a sonic boom likely caused by a high-speed jet.
Officials say it was likely a military jet. They are capable of producing a sonic boom, breaking the sound barrier. But where exactly that jet came from and what was it doing still isn't clear.
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